Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemistry, The National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, P.R. China.
Small. 2012 Mar 26;8(6):930-6. doi: 10.1002/smll.201102060. Epub 2012 Jan 24.
Thermosensitive poly(N-isopropylacrylamide) (PNIPAM)/Au nanoparticle (NP) nanocomposite hydrogels are synthesized by in situ γ-radiation-assisted polymerization of N-isopropylacrylamide monomer aqueous solution in the presence of HAuCl₄·4H₂O. In this reaction, the PNIPAM hydrogels and the Au NPs are formed simultaneously, thus demonstrating an easy and straightforward synthetic strategy for the preparation of a uniform nanocomposite. The results suggest that increasing the monomer content during the preparation of nanocomposite materials can increase the sizes of Au NPs. The effects of irradiation dose and concentration of HAuCl₄·4H₂O on the optical and thermal properties of the hydrogel are also investigated. The PNIPAM/Au nanocomposite hydrogels act as an excellent catalyst for the conversion of o-nitroaniline to 1,2-benzenediamine, and the catalytic activity of the composite hydrogel can be tuned by the volume transition of PNIPAM. The in situ polymerization of monomer and reduction of metal ions initiated by a "clean" and "green" γ-radiation technique can be extended to the efficient synthesis of other nanocomposite materials.
通过在 HAuCl₄·4H₂O 的存在下，用γ射线原位辐照聚合 N-异丙基丙烯酰胺单体水溶液，合成了温敏性聚（N-异丙基丙烯酰胺）（PNIPAM）/Au 纳米粒子（NP）纳米复合水凝胶。在该反应中，PNIPAM 水凝胶和 Au NPs 同时形成，从而展示了一种用于制备均匀纳米复合材料的简单且直接的合成策略。结果表明，在制备纳米复合材料期间增加单体含量可以增加 Au NPs 的尺寸。还研究了辐照剂量和 HAuCl₄·4H₂O 浓度对水凝胶光学和热性能的影响。PNIPAM/Au 纳米复合水凝胶作为 o-硝基苯胺到 1,2-苯二胺转化的优异催化剂，并且复合水凝胶的催化活性可以通过 PNIPAM 的体积转变来调节。单体的原位聚合和金属离子的还原由“清洁”和“绿色”γ-辐射技术引发，可以扩展到其他纳米复合材料的有效合成。
